1. Field of the Invention
The present invention relates to a low-pressure discharge lamp such as a fluorescent lamp, a cold-cathode discharge lamp, or a glow lamp.
2. Description of the Related Art
Recently, low-pressure discharge lamps of the type which have two terminals extending from each base, at right angles to the axis of the bulb, have been used in place of low-pressure discharge lamps of the conventional type which have two terminals extending from each base, parallel to the axis of the bulb. Such a low-discharge lamp is disclosed in Japanese Utility Model Disclosure No. 62-12255. This discharge lamp is characterized in that the two terminals extending from either base take positions symmetrical with respect to the axis of the bulb, and extend from the base in opposite directions.
The discharge lamp of the type described above can be shorter than in the conventional type lamp, since the terminals extend from the bases perpendicular to the axis of the bulb. Further, since the sockets to which the terminals are to be connected can be located at the side of the bases, the lamp device including both the lamp and these sockets can be shorter than otherwise. Moreover, even if the discharge lamp is slightly shorter or longer than it should be, the terminals can, nonetheless, be electrically connected to the sockets.
As has been pointed out, the two terminals extending from either base take positions symmetrical with respect to the axis of the bulb and extend in opposite directions. Therefore, the two power-supply terminals of the socket, which are to be connected with the terminals of the base, must be located on the opposite side of the base. The width of the socket, i.e., the dimension of the socket, along the diameter of the base, is inevitably great. Further, to connect the lamp with the sockets, the lamp must be so moved to have both bases inserted in the sockets, and must also be rotated around its axis so as to adjust the rotational position of the lamp. This is a rather complex manual operation.
Furthermore, if the bases are attached to the ends of the bulb, with the terminals of the first base positioned out of alignment with those of the second base, the terminals of one of the bases may not be electrically connected to the socket, though the terminals of the other base are electrically coupled to the corresponding socket.